Lacquer composition comprising epoxide resin, polyamide resin and cellulose acetate butyrate and article coated therewith



acetate butyrate articles.

2,865,870 LACQUER COMPOSITION COMPRISING EPOXIDE RESIN, POLYAMIDE RESIN AND CELLULOSE ACETATE BUTYRATE AND ARTICLE COATED THEREWITH 7 Raymond G. Pinder, Rochester, N. Y., assignor to Eastman Kodak Company, Rochester, N. Y., a corporation of New Jersey No Drawing. Application October 24, 1955 Serial No. 542,496 4 Claims. (Cl. 260-13) This invention relates to lacquers and more particularly to metallic appearing or pigmented lacquers which are specially suited for application to the surfaces of cellulose Such articles may have been shaped by extrusion, injection or compression molding processes or coated from solvent solutions. Heretofore various lacquer compositions have been formulated for the surface coating of plastics. However, little success has been attained in making a satisfactory metallic appearing or pigmented lacquer for use on cellulose acetate butyrate articles. In such lacquers difiiculty was experienced in adhesion and durability. In fact, such well known highly resistant coatings made from epoxide resins cross-linked with polyamide resins were found to be entirely unsuited for coating cellulose acetate butyrate articles because they failed to adhere to cellulose acetate butyrate.

An object therefore of the present invention is an improved lacquer for use on cellulose acetate butyrate articles which has improved adherence and luster. Another object is an improved pigmented or metallized lacquer having superior adherence to cellulose acetate butyrate surfaces.

Other objects will appear hereinafter.

In accordance with the present invention these and other objects are attained by formulating a lacquer containing as the essential ingredients an epoxide resin, a polyamide resin and cellulose acetate butyrate in a compatible solvent mixture. I have found, whereas the epoxide-polyamide thermosetting resin fails to give satisfactoryadherence to surfaces composed of cellulose acetate butyrate, that the addition of cellulose acetate butyrate to the epoxide-polyamide resin solution before it is heat hardened provides the necessary adhering property to theseresins. It appears the epoxide resin reacts with both the po-lyamide resin and the cellulose acetate butyrate. Thus my invention permits using the highly resistant epoxide resins in this field of cellulose acetate butyrate plastics. Also in accordance with my invention I may add metallic powders or colored pigments to my novel lacquer composition and thus combine the aforesaid durability and adherence with pleasing decorative effects.

My novel lacquer compositions may be prepared according to the following general formulation:

COMPONENT A Preferred Amounts Weight Volume (lbs) (gals) Low Boilin Solvent (T011151) 5. 5o 0. 35 High Boilin g Solvent (High Flash Solvent Naph- 12 80 1 85 13).? u v-L Cllosolve Acetate (CH COOCHtCHZOCZHfi) 12. 20 1. 50 Expoxlde resin 6.00 0.60 Metallic Powder or Pigment 5. 00 0.28

nited States Patent O This general formulation may be varied somewhat by modifying the solvent content to alter drying time or ap plication characteristics. The drying time can be accelerated by increasing the proportion of low boiling solvent to the higher boiling naphtha. If de sired the lowboilers can be from 5 to 12 parts by weight and the high boiler can be from 12 to 5 parts by weight of the high-boilerlow boiler solvent mixture. The organic ester component may be employed in a range of 10 to 15 parts by Weight and the resulting aromatic hydrocarbon-ester solvent combination will give suitable solution with the epoxide resin.

Theepoxide resin is thoroughly dissolved by mixing in the solvents before the metallic powder-orpigment is added. The metallic powder orpigment is then added and thoroughly dispersed in the formulation.

The metallic powde'r dependingjon the desiredappear- 'ance may be metallic bronze powder, leafing or non-leafing, such as aluminum, copper or gold bronze powder. It is finely divided and is preferably of a size shown in the ASTM Standards, .lanua'ryi955, page 131, type 1, Class A.

The pigment may be any of the standard coloring The 'high and low boiling solvents may be employed over a range of amounts between 3 to 12 parts by weight. The ester solvent component may be varied upwards or downwards by 10%.

The cellulose acetate butyrateis dissolved by aid of agitation in the solvent and the polyamide resin is then added with stirring until uniformly dispersed in the mixture.

The component parts A and 'B may be separately packaged" in sealed containers if not to be used promptly. Equal volumes of'component parts A and Bare mixed to gether whenthe lacquer is to be coated onto the cellulose acetate butyrate article.

The lacquer maybe coated onto the cellulose acetate butyrate plastic article by conventional methods, but spraying from a suitable-spray gun is generally the preferred coating method;

. 2,865,870 3 4 Epon 1001 resin. The epoxide resins represent a class oxide, red iron oxide, chrome green, chrome yellow, of condensation polymers and have the typical structure: iron blue, and inert pigments.

I in which n is a whole number from 1 to 5. In general any pigment which has no undesirable reac- The polyamide which serves as a modifier as well as tion with the composition of the lacquer or the article the curing and cross-linking agent cross links with the being coated may be employed.

' reactive hydroxyl and epoxide groups which are widely A decorative firmly adherent coating is thus attainable spaced along the epoxide chain and makes it thermosetby employing my improved lacquer on cellulose acetate ting when heated as described herein. butyrate articles.

The cellulose acetate butyrate employed in the lacquer I claim:

contains from 35 to 39% butyryl groups and 12m 15% 15 l. A heat hardenable lacquer composition, the essenacetylgroups and. serves as the agent to lend to the comtial constituents of which comprise in a solvent therefor position the property of adhering to the cellulose acetate approximately 6 parts of an epoxide resin having the butyrate article. typical structure:

0 Ha CH:

The polyamide resin employed in the B formulation wherein n is a whole number from 1 to 5, approximately .is preferably that sold by General Mills as Polyamide 3 parts of a polyamide resin having the typical structure:

Resin 115. This has a general formula:

HO('C RCNHCH= OHTNH)"H wherein n is a whole number from 5 to 15 and R is an wherein n is a whole number from 5 to 15 and R is an alkylene group having from 5 to 20 carbon atoms, and :alkylene group having from 5 to 20 carbon atoms. A approximately 2 parts of cellulose acetate butyrate conparticularly useful compound is that in which R in the taining from 12 to 15% acetyl groups and to 39% I .above formula is C H butyryl groups.

Other properties of Ep-on 1001 and Polyamide Resin 2. A heat hardenable lacquer composition, the essen- 115 are given in an article entitled Coatings of Poly- 35 tial constituents of which comprise in a solvent therefor .amide and Epoxy Resin Blends by Renfrew et al., lndusapproximately 6 parts of an epoxide resin having the trial and Engineering Chemistry, vol. 46, No. 10, pages typical structure:

. 0\ CH: )H (.311; o\ Cr-CH-CHa--OO+OOCB:CHCHzOO(E -OCHz-C-CH:

L CH3 .J. CHa 2,226 to 2,632, and particularly at page 2,227. wherein n is a whole number from 1 to 5, approximately available on the market as Tenite Butyrate plastic, was

The following examples illustrate the use of my in- 3 parts of a polyamide resin having the typical structure:

vention:

Example 1 Ho -ii-R-ii-NH-omorr,-NH ,H

wherein n is a whole number from 5 to 15 and R is an alkylene group having from 5 to 20 carbon atoms, and approximately 2 parts of cellulose acetate butyrate containing from 12 to 15% acetyl groups and 35 to 39% butyryl groups and a finely divided coloring agent.

3. A heat hardenable lacquer composition, the essential constituents of which comprise in a solvent therefor approximately 6 parts of an epoxide resin having the typical structure:

A camera part of the cellulose acetate butyrate plastic,

formed by the injection molding process and was spray coated with the lacquer made by mixing lacquer components A and B together. The metallic powder in this instance was extra fine leafing aluminum bronze powder. This gave a firmly adherent bright aluminum. appearing finish to the camera part. The coating was oven dried at 170 F. for minutes.

/O\ CIlHs 11 '1 (EH: O\ cHr-Cfi-CHr-O-O-G -ooH,on-orn-0OuO-o-omcfi-cm L .in CH:

Example 2 wherein n is a whole number from 1 to 5, approximately Similar parts were coated and dried in the same 3 parts of a polyamide resin having the typical structure: ner, with the lacquer formed from mixing equal amounts o o of components A and B supra. The metallic powders l g H were respectively copper bronze powder, pale gold bronze powder, antique bronze powder, statutory gold bronze, wherein n is Whole number from 5 t0 15 and R is 811 and brilliant bronze powder. alkylene group having from 5 to 20 carbon atoms, and

E l 3 approximately 2 parts of cellulose acetate butyrate conxamp e taining from 12 to 15% acetyl groups and 35 to 39% Similar parts were coated with the lacquer formed butyryl groups and finely divided aluminum bronze powfrom mixingequal amounts of components A and B, der.

supra. In these instances the metallic powders were re- 4. A cellulose acetate butyrate article having a surface placed with colored pigments. The pigments were recoating thereon of a thermosetting lacquer, the essential .spectively .titanium ,gl ioxide, carbon black, yellow iron constituents of-which comprise the reaction product of 5 6 approximately 6 parts of an epoxide resin having the typiwherein n is a Whole number from 5 to 15 and R is an cal structure: alkylene group having from 5 to 20 carbon atoms, and

0\ (3H3 3H I 3113 0\ CHz-0HCHz-OC 0OHz-CHCH2OOCOOCHz-GHCH2 L (ilHs |n (LE3 wherein n is a whole number from 1 to 5, approximately approximately 2 parts of cellulose acetate butyrate 3 parts of a polyamide resin having the typical structure: having from 12 to 15% acetyl groups and 35 to 39% butyryl groups.

H0 (gR( NHCH2-C HzNH) ,.H

References Cited in the file of this patent UNITED STATES PATENTS 2,190,770 Carothers Feb. 20, 1940 2,633,458 Shokal Mar. 31, 1953 2,703,284 White et a1 Mar. 1, 1955 2,707,708 Wittcoff May 3, 1955 2,710,845 Thompson June 14, 1955 2,715,616 MacIntosh Aug. 16, 1955 OTHER REFERENCES Renfrew et a1.: Industrial and Engineering Chemistry, volume 46, N0. 10, pages 2226 to 2632.

Chemical and Engineering, volume 31, November 9, 1953, page 4680. 

1. A HEAT HARDENABLE LACQUER COMPOSITION, THE ESSENTIAL CONSTITUENTS OF WHICH COMPRISE IN A SOLVENT THEREFOR APPROXIMATELY 6 PARTS OF AN EPOXIDE RESIN HAVING THE TYPICAL STRUCTURE: 